Infrared sensors are used to detect equipment and personnel that would otherwise be invisible either because of camouflaging or due to an insufficiency of visible light. The infrared sensors are able to profile the thermal topography of a region through amplification and analysis of the light emitting in the infrared region of the light spectrum. Temperature deviations of less than 1/2 F above the ambient temperature, can be discerned. The infrared technology is often incorporated by the military into an array of weapon systems to spot, tract and align guidance systems and sights of a weapon onto a radiant heat source, such as equipment or personnel. Thermal imaging using infrared detectors is accurate enough to identify not only the position of the radiant heat source, but also details specific enough to distinguish signature morphological features. To practice identifying and shooting potential targets the military uses training aids that simulate real life equipment and personnel. The training aids can be two or three dimensional, full or scalar reproductions of the simulated objects. To simulate the heat actually generated by the equipment or personnel, the training aids or targets must themselves give off a comparable amount of energy. A method to affect this thermal image is to use targets that are covered with a type of electric blanket, where the blanket is heated and shaped so as to imitate the heated, more distinguishing thermal surface features of the simulated object.
Thermal targets are typically erected on a firing range for gunnery practice at some future date. On the range a number of practical problems have been encountered that require inexpensive solutions. Thermal targets simulating large pieces of equipment tend themselves to be both expensive and massive, requiring several people and multiple pieces to assemble. Thermal targets using an electrical system to produce a thermal image are frequently sensitive to climatic conditions, and are on the whole not sufficiently dependable. The target should be able to be hit with a number of rounds and still retain its thermal image to the extent that its thermal features or signature is still intact and discernible. The target must hole cleanly, independent of the shell size, and be fire resistant.